Horace Gwynne Allen (July 27, 1855 – February 12, 1919) was an American lawyer and politician.

Horace and Grace Allen had three daughters, Eleanor, Beatrice, and Rosamund.

[8] He lost the 1891 Boston mayoral election to Democratic incumbent Nathan Matthews Jr. 63% to 36%.

[4] Allen considered running in 1892, but withdrew from consideration shortly before the party convention.

[6] In 1896, Allen was appointed to the Boston transit commission by acting governor Roger Wolcott.